Small Animal Imaging Core Abstract As the preclinical imaging has been increasingly used in drug discovery and development, the Small Animal Imaging (SAI) core has become an indispensable component in the proposed CCNE grant, with the goal of providing cutting edge imaging techniques and expertise to facilitate nanoparticle technology development in each project. The SAI core has been long involved in the CCNE projects since the CCNE phase I, and has made substantial contributions in the nanotechnology development by providing comprehensive support on in vivo optical imaging, microCT imaging, MR imaging, PET/CT, SPECT/CT, ultrasound imaging, and the combined multimodality imaging technique on ten projects in the past two CCNE phases. On the other hand, the imaging core has had significant expansion in the past ten years. Our imaging equipment has increased from one MRI and one optical system in 2004 to current eleven imaging systems covering almost all the animal imaging modalities. The recent relocation to the new building has expanded the facility space to more than 40,000 sq ft with upgraded lab space. The new cyclotron and radiochemistry facility further enhanced the molecular imaging capability, enabling on-demand imaging probes produced nearby and novel imaging probes development. Faculty recruitment on radiochemistry and radiopharmacy has added the imaging core with the expertise on radiosynthesis and translational imaging studies. Operated as a recharge core facility, the imaging core has also made considerable enhancement in the infrastructures on scheduling, registration, animal support, protocol development, system maintenance, and billing. Leveraging on these impressive resources and capacities the SAI core aims to provide advanced imaging technology to facilitate the proposed projects. Two specific aims have been proposed: 1) Optimize optical and PET imaging methods for biodistribution studies; 2) Develop multimodality imaging approach to evaluate cancer treatment efficacy. Specifically, optical imaging and PET/CT imaging will be used to characterize developed nanoparticles or nanodrugs in terms of PK and biodistribution in the four projects. In addition, multimodality imaging, including optical, ultrasound, microCT, and PET/CT imaging will be used to evaluate treatment efficacy in project 1-4. Overall, we believe that the enhanced imaging capability and infrastructure in the SAI core will greatly benefit the nanodrug development, and facilitate the success of the proposed projects.